/*
Consider the set S(r) of points (x,y) with integer coordinates satisfying |x| + |y| ≤ r. 
Let O be the point (0,0) and C the point (r/4,r/4). 
Let N(r) be the number of points B in S(r), so that the triangle OBC has an obtuse angle, i.e. the largest angle α satisfies 90°&lt;α&lt;180°.
So, for example, N(4)=24 and N(8)=100.

What is N(1,000,000,000)?

Anser:
Time:
*/
package main

import (
	"fmt"
	"time"
)

func main() {
	tstart := time.Now()



	tend := time.Now()
	fmt.Println(tend.Sub(tstart))
}